Development of Basic Technologies for Drop-Tower Experiments on Vertebrates

Abstract

The purpose of this study is to evaluate several kinds of stress factors for small animals used with ground-based experiment facilities such as drop towers, parabolic flights, or centrifuges; and to mitigate the stressors, with the exception of gravity, in order to increase the scientific value of the experiment data and improve animal conditions. In the first step, we conducted experiments in a drop tower (Micro-Gravity Laboratory of Japan; MGLAB, Toki-city) and examined the following factors. 1) Environmental factors: Monitored and controlled environmental factors, such as temperature, humidity, oxygen and carbon dioxide concentration. 2) Evaluation of stress on animals: Biochemistry, in situ hybridization histochemistry, behavior, and physiology. From these results, we are able to estimate the degree of stress in drop-tower experiments to be level two on a scale of one to five level from the mildest state. The data and know-how we acquired will be summarized as a handbook and published for animal experiments employing the drop tower.